writer：Min Zhang , Hengrui Zhang ，Jie Feng , Yunlong Zhou , Bailiang Wang
keywords：antimicrobial agent，biofilms infections，gold nanobipyramid,chiral glutamic acid,photothermal therapy
source：期刊
Issue time：2020年
Sepsis and implant-related bacterial infections are mainly caused by Gram-positive bacteria accompanied withthe notorious drug resistance and biofifilms formation. Although the recently concerned photothermal therapy(PTT) shows good performance in killing of planktonic bacteria and removal of biofifilms, the issue of potentialthermal damage to normal tissue is urgent to be solved due to the non-targeting to bacteria. Here, we constructeda chiral glutamic acid functionalized gold nanobipyramids (Au NBPs) for enhanced PTT against bacterial andbiofifilms infections based on both chemical and physical interactions with bacteria. Specififically, the conjugationof D/L-glutamic acid (D/L-Glu) obviously enhanced the targeting and interactions of Au NBPs with bacterial cellwall leading to the biological restriction of nucleic acids. While the sharp tips and small size of Au NBPs enabledthe penetration into bacterial cell wall and biofifilms for cicada''''s wings bionic damage to bacterial cell wall andleakage of components. Furthermore, antibacterial mechanism examination confifirmed the chemical and physical effffects of D/L-Glu and nanobipyramids structure leading to the considerable DNA and nucleic acids leakage,which was greatly enhanced during PTT treatment. Both in vitro and in vivo antibacterial and anti-biofifilmsmeasurements verifified high effiffifficiency in killing of bacteria and eliminating of biofifilms through a synergisticchemotherapy, physiotherapy and PTT functions. Furthermore, the quick targeting of chiral Au NBPs to thebacteria and penetrating into extracellular matrix effffectively avoided the nonspecifific damage to normal cells.Therefore, this work provides a novel strategy to combat bacterial and biofifilms infections in a more smart wayowing to the chiral amino acid modifification and synergistic antibacterial effffects.